Two distinct cDNAs for human IMP dehydrogenase.

Y Natsumeda; S Ohno; H Kawasaki; Y Konno; G Weber; K Suzuki

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PubMed · 1969416

Two distinct cDNAs for human IMP dehydrogenase.

Y Natsumeda·S Ohno·H Kawasaki·Y Konno·G Weber·K Suzuki

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Abstract

IMP dehydrogenase (EC 1.1.1.205), the rate-limiting enzyme of de novo GTP biosynthesis, is a promising target in antileukemic chemotherapy. We have isolated two distinct cDNA clones (types I and II) encoding IMP dehydrogenase from a human spleen cDNA library. Both clones encode closely related proteins of 514 residues showing 84% sequence identity. Northern hybridization analyses of poly(A)+ RNA from human normal leukocytes and human ovarian tumors demonstrated a striking contrast in mRNA expression in that type I mRNA is the main species in normal leukocytes and type II predominates over type I in the tumor. This is the first report suggesting the existence of two distinct types of human IMP dehydrogenase molecular species which may have different sensitivities to the drugs targeted against IMP dehydrogenase.

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Amino Acid Sequence Base Sequence Cloning, Molecular DNA Escherichia coli Humans IMP Dehydrogenase Isoenzymes Ketone Oxidoreductases Molecular Sequence Data Nucleic Acid Hybridization Oligonucleotide Probes Restriction Mapping Sequence Homology, Nucleic Acid Spleen Comparative Study Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S.

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Y Natsumeda, S Ohno, H Kawasaki, Y Konno, G Weber, K Suzuki. 1990-03-25. Two distinct cDNAs for human IMP dehydrogenase.. https://pubmed.ncbi.nlm.nih.gov/1969416/

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